Hydrogen gas is used in a variety of industrial applications. For instance, hydrogen is often used in the creation of ammonia for fertilizer, for the conversion of heavy petroleum sources to lighter fractions through a process called hydrocracking, for the production of nickel-hydrogen batteries, and for several other applications. Hydrogen is a clean burning fuel and a source of energy for fuel cells.
In order to obtain hydrogen for use in such applications, hydrogen can be produced through an assortment of techniques, including through the electrolysis of water, the reaction of a metal with an acid, the steam reformation of natural gas, the partial oxidation of hydrocarbons, and through several other methods.
Indeed, in some instances, hydrogen gas is formed through the electrolysis of water. In such instances, water or an alkaline water solution, is placed in an electrolytic cell comprising an anode and a cathode. Then as an electrical current is passed between the anode and cathode, hydrogen is produced at the cathode by reduction of water and oxygen is produced at the anode by water oxidation. For instance, the two electrode half reactions for traditional alkaline water electrolysis are:2OH−→H2O+½O2+2e−  Anode:2H2O+2e+→2OH−+H2  Cathode:
Moreover, the overall reaction of traditional alkaline water splitting is:H2O→H2+½O2  Overall:
While the production of hydrogen gas through the electrolysis of water has been found to be a useful process, it is not without its shortcomings. For instance, the theoretical open cell voltage for the oxidation and reduction of traditional water electrolysis is about 1.23 volts (“V”) and the operating voltage is typically ≥1.8V at practical current densities when the overvoltage is taken into account. As a result, the production of hydrogen through such traditional electrolytic methods may be relatively energy-intense, inefficient, and expensive. Therefore a lower voltage less energy intensive process will be attractive for production of hydrogen.